Device for equalizing printing impressions



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Nov. 2,1926. 1,605,645

C. CHISHOLM vavrcn Fon EQUALIZING PRINTING ruvnsssrous Filed April 27.1925 2 sneetefshen 2 I Z auvent Q7' 76m: {fdr-20% @Ronny Patented Nov.2, 1926.

UNITED NSTATES f imams PATENT oEFlcE.

CLIFTON CHISHOLM, OF CLEVELAND, OHIO, ASSIGNOR TO THE AMERICAN MULTI-GRAPH COMPANY, 0F CLEVELAND, OHIO, A CORPORATION OF OHIO.

DEVICEKFOR EQUALIZING PRINTING IMPRESSIONS.

Application led April 27, 1925. Serial No. 25,976.

My prior Patent No. 1,451,204 issued April 10, 1923, to the AmericanMultigraph Company shows a printing form adapted for mounting on arotary drum and comA prising a sheet metal plate having upstandingoverhanging rows of projections which are surmounted by embossedprinting strips having inwardly flanged edges adapted to overhang theprojections. Such a flexible :torm may be readily mounted, for example,on a multigraph drum and print through an inking ribbon extending overthe form. In such operation, the printi-ng lines lie parallel with theprinting aXisand coact one at a time with a roller platen to impresspaper between them. It results from this that very short lines, such assometimes come at the end of a. paragraph or in the salutation, make aheavier impression than the body of the form where the lines are ofapproximately the same length.

The object of this invention is to provide a simple attachment adaptedfor mounting on this flexible blanket and serving to relieve thepressure on the short lines. To this end, I have provided a devicehaving two parallel strips connected at one end, and separated a shortdistance, the understrip being adapted to rest on top of a row ofprojections, and having means to hold yit on the blanket and the upperstrip adapted to overlie the ribbon. When the upper strip is pressedagainst the ribbon, during the printing impression, its outer surfacestands the same heightto-the-paper as the ribbon normally stands when itengages the form.

When kmy pressure equalizer is inserted in alignment with a short line,the printing pressure at such time is taken partly at the short line andpartly by the equalizer,with the result thatpractically the same supportfor the pressureis provided as in a line of normal length. andVaccordingly the short lines print with the same depth of impression asthe other lines.

The base member of my equalizing device may be provided with inwardflanges to underhang the projections on which the strip rests or withoutward flangesl to underhang the projections of adjacent rows. Ineither case. however, the base member rests on top of the row ofprojections which carries the short embossing printing strip. Each formis illustrated herein and is covered by the claims hereof.

In the drawings Fig. l is a vertical section through a multigraphmachine equipped with my flexible blanket and one of my equalizers; Fig.2 is a plan of a portion of such drum showing one ot the equalizers inplace; Fig. 3 is a cross-section on the line 3 3 of Fig. 2; Fig. 4 is aperspective of the equalizer having the inward edge flanges as shown inFig. 2; Fig. 5 is an enlarged end View of the equalizer shown in Fig. 4;Fig. 6 is an enlarged cross-section of the blanket, embossed strips andone of my inwardly flanged equalizers on a flat form; Fig. 7 is asimilar cross-section showing the equalizer with the outward flanges;Fig. 8 is a perspective of the equalizer with outward flanges; Fig. 9 isa cross-section through a portion of a railed segment usual in themultigraph, equipped with my blanket and each form of equalizer.

In Figs. 2, 3, 6, 7 and `9, the numeral 10 indicates the flexibleblanket, which may well be of' the form substantially shown in my patentreferred to, and comprises a sheet of metal having rows ot upstandingbuttons 11, which are connected at opposite edges in the line of the rowwith upstanding corrugations 12, the edges of the buttons at the sidesof the corrugation 13 being disconnected from the body of the plate andstanding some distance above it. Such form of type holder is more fullydescribed in Patents No. 1,438,584 and No. 1,438,582, issued December12, 1922, on applications of William J. Demming and Burnie J. Craigrespectively.

Mounted on the rows of buttons are embossed printing strips 20, eachmade of sheet metal and having upstanding projecting printingcharacters, and having inwardly extending edge flanges which extendbeneath the overhanging buttons, and there* by hold the strip in place.vA holder having projections with such strips mounted thereon is coveredin my Patent No. 1,438,- 580 issued December 12, 1922. Such strip may beproduced in any suitable machine, as for'eXample that illustrated in myapplication No. 535,311, filed February 9, 1922, which also claims thestrip per se.

Referring now to Figs. 1 to 6 inclusive, my equalizer is shown ascomprising a lower or base strip y30 having inwardly flanged edges 31,and an upper or pressure strip 32 tying; a short distance above thestrip 3G,

and connected with it at one end. To effect the connection, I prefer tomount a filler block 33 beneath the body of the base strip 3() adjacentone end; to offset downwardly the end portion of 'the pressure strip 32as at 34, and to extend two rivets through the top strip. the bottomstrip and the tiiler block. These rivets may be counter sunk in thefiller block and the top `strip.

The base strip is made ot any suitable metal oi suiiicient stiffness tohold its shape, while the top strip is of a spring steel and has atendency to spring slightly Vaway from the bottom strip.

In use, the equalizer is slipped endwise over the row of buttons whichcarry the short lines desired to be equalized, the joined end of theequalizer being beyond the blanket. The ribbon, designated A, is thenpassed over the body of the 'torni but beneath the top strip of theequalizer. in this position the top surface of the equalizer is inthesame plane with the top of the rib-l bon where it overlies the shortline, as clearly illustrated in Fig, 3. Accordingly, whenever theprinting pressure comes on this line, the pressure is substantially thesame as if it were of full length.

By making the top strip of steel, it does not .bind the ribbon, exceptat the instant ot impression, and accordingly the ibbon is tree to beperiodically fed during the rotating of the machine. As is usual in themultigraph, such feed taking place at a time when the form is out otcoaction with the platen. i

In the form of equalizers shown in Figs. 7 and 8, the top strip 32 isidentical with that just described, but the base strip 36 instead ofhaving its langes extending diagonally inward, has downward, slightlydaring portions 87 at the bottoms oi which are outward iia-nges 38. Thetwo flanges 3.8 are adapted to underlie the projections of adjacent rowsof buttons instead of the projections on which the body of strip rests.The top strip is riveted to the body ot the bot-tom strip as at 3.5 byrivets which pass through these two strips and through a reinforcingblock. This reinforcing block is shown at 89V in Fig. 8 when the sides3T and the flanges 38 are shown as cut away at this ,end to allow awider filler block.

In the form of equalizer just described, the base strip may be readilymanufactured by a single operation oit stamping, but it has adisadvantage that it is not applicable to single space work on theblanket, but requires vacant rows oi buttonslon opposite sides of therow carrying the short line.

It will be seen that my equalizing device, madein either form shown, isadapted tot ready use with the flexible blanket mounted on its supportwithout any change whatever in either the support, the blanket or theembossed strips. Such equipped blanket may -be mounted -on a smooth drumshown at i0 in Fig. l; on a plate as shown at 4l in Figs. 6 and 7, or onrails 42 ot a multigraph .drum as shown in Fig.

Fig. 1 illustrates a machine similar to inultig'aph having a segment 40clamped on a skeleton rotary driving shaft 4.15, and a pair ot ribs bonspools i6 mounted within the drum to carry the ends ot the ribbon. Theform covered by the ribbon coactsl with the rul ber faced roller platenat?. A suitable mechanism not shown may `feed this ribbon periodicallyby rotating one spool or the other. For a Jfurther description of such amachine, and jarticularly ot means for feeding the ribbon, reference maybe made to Patent No. 997,28?, issued July l0, llll, to the AmericanMultigraph Company.

Having thus described my invention, i claim:

l. The combination ot a type hoider liavi* ing rows ol overhangingprojections, embossed printing strips mounted on the projections ot' thediilierent rows and havingl inwardly projecting edge flanges to extendbeneath said projections, and an equalizing device 'for shortlinescomprising a body adapted to rest on top of a row oi:l projections andprovided with means Jfor holding it in place thereon, and a stripparallel with the body and a short distance above it, connected with itbeyond the edge o' the type form, said upper member adapted to overlie aribbon which passes over the type form and over the body of said device.

2. The combination oi' a holder having projections, embossed printingstrips resting1 on such projections and having inward edge flangesextending beneath them, an equalizing device comprising a base memberadapted to rest on top of a projection and having edge flanges forholding it in place, and a top member secured at one end to the basemember and adapted to overlie a ribbon.

3. The combination of a type holder having raised portions, embossedprinting strips mounted on the raised portions, and an equalizing devicefor short lines comprising a Abody adapted to reston a raised portionand provided with means for holding it in place thereon, and a stripparallel with the body a short distance above it and connected with itbeyond the edge form, the combined thickness of the body and top stripbeing equal to the thickness of an embossed strip plus the height ot theprinting characters above the body ot such embossed strip.

li. The combination of a type holder hav ing overhanging projections,embossed drum la mounted on a 'l Uli) llt)

imi

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printing strips mounted on the projections and having inwardlyprojecting edge anges to extend beneath said projections, and anequalizing device for short lines comprising body adapted to rest on aprojection and provided with edge flanges :tor holding it in placethereon, and a strip parallel with the body a short distance above itand connected with it beyond the edge o'l' the type form, said top stripbeing of spring material to enable it to automatically relieve pressureon the ribbon when it is out of printing coaction.

5. The combination of a printing couple adapted to have rollingcoaction, a remov able type holder mounted on one memberof the typecouple and having upstanding projections arranged in rows, embossedprinting strips mounted on said projections, an inking ribbon adapted tobe extended across such strips, and a pressure equalizer mounted on arow of projections in alignment with a short strip and having a topstrip adapted to overlie the ribbon, said top strip standing at the sameheight-topaper as the ribbon over the short strip.

l 6. An equalizing device of the character described. comprising a bodystrip having flanged edges, and a top strip some distance above the bodystrip and connected to it at one end.

7. An equalizing device of the character described combining a bodystrip equipped with means for holding it in place and the top strip somedistance above the body strip and made of spring material and connectedat one end to the body strip.

8. In a device of the character described, comprising a base striphaving flanged edges, a spring metal top strip having a downwardlyoffset portion at one end, and means for connecting said odset portionwith the end portion of the base strip.

9. In a device of the character described, the combination of a basestrip having flanged edges, a top strip some distance above the basestrip for the greater portion of its length, the top strip and basestrip being in engagement adjacent the end, and rivets passing throughsuch engaging portions.

10. An equalizing device of the character described comprising a basestrip having inwardly flanged edges, and a top strip some distance abovethe base strip and connected to it at one end.

1l. In a device of the character described, the combination oi' a basestrip having inwardly flanged edges, a top strip of spring steel somedistance above the base strip for the greater portion of its length, thetop strip being downwardly offset adjacent the end, and rivets passingthrough suchend portion to connect the two strips together.

In testimony whereof, I hereunto affix my signature.

cLrrropN cHisHoLM.

